The goal is to convert a Bitmap
to a byte []
, pass it between activities in a Bundle
of data, then reconvert it back to a Bitmap
at a later stage for display in an Imageview
.
The issue is that whenever I try this, I just get a null bitmap and the non-descriptive, unhelpful log output:
12-07 17:01:33.282: D/skia(2971): --- SkImageDecoder::Factory returned null
I have looked at the following solutions:
Solution supplies the bitmap to byte[] code used
Highlighted that copyPixelsToBuffer() is essential over .compress
(Especially seeing as it is not necessary in this case).
I have run up the following test case which definitely narrows down the problem to the converting and restoring code. Based on my debugging, there is correct decoding, the byte array is the correct size and full, Bitmap configs are forced to be the same, decodeByteArray
is just failing:
package com.example.debug;
import java.nio.ByteBuffer;
import android.os.Bundle;
import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.Bitmap.Config;
import android.graphics.BitmapFactory;
import android.util.Log;
import android.view.Menu;
import android.widget.ImageView;
import android.widget.RelativeLayout;
public class MainActivity extends Activity {
RelativeLayout rl = null;
RelativeLayout.LayoutParams rlp = null;
ImageView ivBef = null;
ImageView ivAft = null;
Bitmap bmBef = null;
Bitmap bmAft = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// TEST
BitmapFactory.Options bmo = new BitmapFactory.Options();
bmo.inPreferredConfig = Config.ARGB_8888;
bmBef = BitmapFactory.decodeFile("/mnt/sdcard/Debug/001.png", bmo);
byte[] b = bitmapToByteArray(bmBef);
bmAft = BitmapFactory.decodeByteArray(b, 0, b.length, bmo);
LinearLayout ll = new LinearLayout(this);
ivBef = new ImageView(this);
ivBef.setImageBitmap(bmBef);
ivAft = new ImageView(this);
ivAft.setImageBitmap(bmAft);
ll.addView(ivBef);
ll.addView(ivAft);
setContentView(ll);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}
public static byte[] bitmapToByteArray(Bitmap bm) {
// Create the buffer with the correct size
int iBytes = bm.getWidth() * bm.getHeight() * 4;
ByteBuffer buffer = ByteBuffer.allocate(iBytes);
// Log.e("DBG", buffer.remaining()+""); -- Returns a correct number based on dimensions
// Copy to buffer and then into byte array
bm.copyPixelsToBuffer(buffer);
// Log.e("DBG", buffer.remaining()+""); -- Returns 0
return buffer.array();
}
}
The before Imageview
correctly displays the image, the after ImageView
shows nothing (as you would expect with a null bitmap
You are passing Bitmap into Intent and get bitmap in next activity from bundle, but the problem is if your Bitmap/Image size is big at that time the image is not load in next activity.
Use below 2 Solutions to solve this issue.
1) First Convert Image into Byte Array and then pass into Intent and in next activity get byte array from Bundle and Convert into Image(Bitmap) and set into ImageView.
Convert Bitmap to Byte Array:-
Bitmap bmp = BitmapFactory.decodeResource(getResources(), R.drawable.ic_launcher);
ByteArrayOutputStream stream = new ByteArrayOutputStream();
bmp.compress(Bitmap.CompressFormat.PNG, 100, stream);
byte[] byteArray = stream.toByteArray();
Pass byte array into intent:-
Intent intent = new Intent(this, NextActivity.class);
intent.putExtra("picture", byteArray);
startActivity(intent);
Get Byte Array from Bundle and Convert into Bitmap Image:-
Bundle extras = getIntent().getExtras();
byte[] byteArray = extras.getByteArray("picture");
Bitmap bmp = BitmapFactory.decodeByteArray(byteArray, 0, byteArray.length);
ImageView image = (ImageView) findViewById(R.id.imageView1);
image.setImageBitmap(bmp);
2) First Save image into SDCard and in next activity set this image into ImageView.